Thoracic Endovascular Aortic Repair versus Optimal Medical Treatment in Patients with Type B Intramural Hematoma: A Meta-Analysis

Purpose: We intended to study the effect of thoracic endovascular aortic repair (TEVAR) and optimal medical treatment (OMT) on type B intramural hematoma (BIMH). Methods: We searched PubMed, EMbase, Cochrane Library, and China National Knowledge Infrastructure databases that compared TEVAR and OMT in patients with BIMH. Two authors independently assessed the risk of bias using the Newcastle–Ottawa Scale. The rate ratio (RR) and 95% confidence interval were used to calculate the outcome. The primary endpoints were aortic-related death and regression/resolution. Secondary endpoints were all-cause death, progression to dissection, and secondary intervention. Results: Eight observational studies were included in the analysis. TEVAR reduced aortic-related death (RR 0.22, 95% CI 0.08–0.56, P = 0.002, I² = 24%) and promoted hematoma regression/resolution (RR 1.48, 95% CI 1.05–2.10, P <0.05, I² = 71%) compared to OMT. Moreover, TEVAR was associated with a reduction in progression to dissection (RR 0.32, 95% CI 0.13–0.81, P <0.02, I² = 39%) and secondary intervention (RR 0.18, 95% CI 0.09–0.37, P <0.00001, I² = 38%) compared to OMT. However, all-cause death has no significant difference between the two groups (RR 0.45, 95% CI 0.17–1.19, P = 0.11, I² = 58%). Conclusions: The results of this meta-analysis suggested that TEVAR is an effective treatment for BIMH, which can delay the progression of intramural hematoma and promotes regression/resolution. More research about indications of TEVAR is still needed.